Heat exchanger



May 14, 1940.

H. J. FINDLEY HEAT EXCHANGER Filed May 12, 1958 IN VE'N TOR fi rv eo.J'. FINLLEX BY W I ATTORNEY heater core.

Patented May'14, 1940 UNITED "STATES PATENT oFFic-e Eaton ManufacturingCompany,

Cleveland,

Ohio, a corporation of Ohio Application May 12, 1938, Serial No. 207,478

Claims.

This invention relates to vehicle heating systems and particularlyconcerns means for use in conjunction with hot water heaters for preventing undesirable noises resulting from gurgling oi the water in saidheaters.

The primary object of this invention is the provision of means inconjunction with hot water heaters for eliminating. thegurgling noisewhich usually results due to circulation of water with aerated fluidthrough the radiator of the heating system.

Investigation as to the cause of this sound has established it to bemade by air bubbles locked in the heating fluid that is circulated underpressure to the inlet tank of the heater radiator, and as the fluidemerges from the core passages into the outlet tank there is a rapidexpansion in the reduced pressure area as the air separates from thewater producing a gurgling sound as each air bubble is freed to the topof the outlet tank. Research directed toward the solution of thisproblem has established that the most practical way to cure thisannoyance is to prevent any aerated fluid from being circulated throughthe a A further object of this invention is the provision of an airseparating means for use in conjunction with a conventional hot waterheater radiator of an automotive vehicle that substantially prevents anycore resonance resulting from gurgling of the water during the operationof said heater.

A further object of this invention is the provision of means adaptableto conventional hot water heaters as used on ordinary motor vehiclesthat substantially prevents circulation of air through said heaters. v

A still further object of this invention is to provide in combinationwith an automotive vehicle having aninternal combustion engine, a watercirculating system therefor, and a heating device deriving heat fromsaid system for warming the passenger compartment of said vehicle,

an air separating means adapted to be serially connected in the supplyside of said heater and' conjunction with a hot water heater for thepassenger compartment of an automotive vehicle, adapted to be seriallyconnected to the inlet side of said heater, and having an air escape conduit in communication with the discharge side of said heater.

Other, objects and advantageous features will become apparent whenconsidered in conjunction with the-following description and theaccompanying drawing, wherein like numerals designate like parts in theseveral views.

Fig. 1 is an elevational view partly in section illustrating a heatercore with supply and discharge pipes leading'therefrom and incorporatingthe subject matter of this invention, and

Fig. 2 is a partly cut-away elevational view of the device of thisinvention removed from the' heater circuit of Fig. 1, and

Fig. 3 is a top plan view of the cylindrical tank of Fig. 2, and

Fig. 4 is a longitudinal view through an engine compartment and asection of the passenger compartment of an automotive vehicle andheating device depicting one form of this invention joined in the heatercircuit. v

In Fig. 1 a conventional hot-water heater core III has tanks ll and 12at the ends thereof with which supply and discharge pipes l3 and M areconnected, respectively. Adjacent the inlet tank II and in the supplypipe [3 a cylindrical tank I5 is serially connected. That is to say,inlet pipe I6 of cylindrical tank I 5 is connected to supply pipe l3,and outlet pipe I! of tank I5 is joined to supply pipe I 3 ahead of theheater core. A centrally located conduit on the upper axis of tank l5preferably has its free end joined as at 2| to discharge pipe 14 andextends a short distance on the axis thereof to create an aspiratoreflect by the reduced flow area past its mouth. The operation of tank I5is as follows:

Inlet pipe I6 is tangentially joined to tank l5 near the top portion ofthe cylindrical section and similarly outlet pipe IT is tangentiallyjoined to the tank adjacent the lower portion thereof, as best shown inFigs. 2 and 3. A cover member IQ of hemi-spherical shape is sealinglysecured to the cylindrical portion of the tank, and axially located atthe upper extremity of the cover memher a pipe 20 of small bore relativeto the inlet pipe 16, leads from the tank. Water enters the tank throughinlet pipe l6, which is fed by the heater. supply pipe l3, and beingtangentially joined to the outer periphery of the tank a rotary motionisimparted to the fluid. The water having a greater specific gravitythan the entrapped air will flow by centrifugal force to the outerregions of the tank and descend spirally toward the bottom of the tank,while the air being lighter than the "water will tend to separate fromthe water and remain near the axis of the tank, and in the reducedpressure area existing in the tank will rise to the top portion of thetank-where it will be vented through the by-pass tube 20. As shown inFig. 1, this by-pass' tube isshunted to the heater core discharge pipel4 by'means of a suitable fitting 2|. It will be 'evident now thatsubstantially air-free water will flow from the tank outlet pipe I! tothe supply pipe l3 and into the heater tank H and core 10. Further,

the fluid flow in discharge pipe ll being restricted in area by theinsertion of by-pass tube shunted into the axial bore thereof willcreate an aspirator effect at the mouth of the tube and produce asuction in the tube tending to draw the free air from the air separatingtank IS. The relative sizes of inlet pipe 16 and by-pass tube 20 andtheir respective locations effectively prevents any short-circuiting ofthe heating fluid around the core, by providing a low pressure exit forthe air, for example, one embodiment of the invention uses a 95 inletand outlet tank tub s and air by-pass tube. Obviously the inlet tube 16may enter the tank l5 parallel to the major axis thereof and tangentialto the outer periphery of the tank so as to slow up the. water flow asit enters the tank and increase the tendency of the air and water toseparate before the water begins its centrifugal spirally downward path.This construction would only necessitate a right angle rotationdownwardly of inlet pipe l6 as viewed in Fig. 2. In the previouslydescribed construction the air by-pass tube has been described as beingjoined to the discharge pipe of the heater merely because it provided asource of lower pressure or suction to effect the withdrawal of air fromthe air separating tank 15. Obviously the air by-pass tube may be joinedwith any other convenient source of suction existing in the enginecirculating system. an example of which is shown in the followingclescription.

In Fig. 4 a hot-water heating device 23 is shown connected to the enginecirculating system of an automotive vehicle embodying the subject matterof this invention. The heater 23 is mounted on the passenger side of thedash 24 in a conventional manner, and the air separating tank l5 forconvenience and conservation of room under the cowl is mounted on theengine side of the dash. The inlet pipe l6 of the tank I5 is shownconnected to the cylinder head 25 on the pressure side of the enginewater pump 26. As previously mentioned water then enters the separatingtank l5 at a tangential opening and centrifugally separates itself fromany entrapped air through the spirally downwardly path assumed by thefluid flow. From the tangential outlet pipe l1. air-free water flowsthrough the heating device 133 and out the discharge pipe 14 back to thesuction side of the water pump. In this Showing air by-pass tube 20extends from the top of the tank i5 and is connected to the inlet orsuction side of the pump 26, whereby an aspiraior effect is created atthe outlet of tube 20 so as to remove air separated from the water intank i5 and accumulated in the dome-like top thereof. Alternatively. asshown by dotted lines 20', the air by-pass tube 20 may be joined at theoutlet end with the upper tank of the car radiator if desired. In thishook-up the tube 20 would be above the water level in the top tank andin a region of atmospheric pressure due to the venting afforded by theconventional overflow tube incorporated therein. The requisite amount ofsuction would be available at this point because of the relatively lowervalue of the atmospheric pressure in relation to the pressure existingin the fluid circuit through the heater.

Since many changes can be made in the formal arrangement andcombinations of parts without departing from the spirit and broad scopeof this invention, it is not the intention to be limited to the specificconstruction and modification shown, but to include all possiblemodifications fairly within the scope of this invention and limited onlyby the appended claims.

What I claim is:

1. The combination with a hot water heater core having header tanks atthe ends thereof with which supply and discharge pipes are connected.respectively, of a tank for separating air from water for the supplypipe of said heater core. comprising inlet and outlet pipes extendingfrom adjacent the upper and lower portions of said air separating tank,respectively, and an air venting tube extending from the upper portionof said tank to the interior of said heater discharge pipe substantiallyon the axis thereof and facing in the direction of fluid flow.

2. The combination with a hot water heat exchange core having a headertank at either end thereof with which a supply and discharge pipe areconnected, respectively, of an air separating means comprising a tankhaving a tangentially arranged inlet and outlet in communication withthe upper and lower portions thereof. respectively. said air separatingtank member adapted to be connected in series with said heat-exchangecore supply pipe, and a relatively small air bypass tube extending fromthe upper portion of said air separating tank and in communication withthe said heat exchange core discharge pipe substantially on the axisthereof and facing in the direction of fluid flow.

3. The combination with a hot water heatexchange core having top andbottom header tanks and discharge and supply pipes leading therefrom,respectively, of a cylindrical tank having inlet and outlet pipes influid communication with the tank adjacent the top and bottom portionsthereof and serially connected to said heat exchanger supply pipe, and aby-pass pipe shunted between the uppermost portion oi said cylindricaltank and the discharge ozpe of said heat exchanger substantially on theaxis thereof and in the direction of fluid flow. when-by air isdelivered through said by-pass pipe and airfree fluid delivered to saidheat exchange core supply pipe.

4. A water gurgle eliminator for a hot water heater core for thepassenger compartment of a motor vehicle, comprising in combination aheatexchange core having supply and discharge pipes connected therewith,an air-separating tank ineluding inlet and outlet pipes tangentiallyjoined to said tank adjacent the upper and lower portions thereof,respectively, said tank inlet and outlet pipes connected in series insaid heater core supply pipe. and an air vent conduit shunted betweenthe uppermost portion of said tank and said heater core discharge pipesubstantially on the axis thereof and disposed in the direction of fluidflow.

5. In a heat exchange core of the hot water type with which areconnected supply and "l charge pipes, means to remove air from said wply pipe and by-pass the same to said tliwm-wpipe. comprising a tankmember havine mint d i lglf HOWARD J. FINDLEY.

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